S100, if you dig enough you might find out what kind
of military system would have either spilled over
into the 5Mhz band or didn't have enough receive filtering itself.
The 5MHz bands are consecutive for WCMDA in the rest of the
world, but in US there are some military,etc stuff in
the middle, needing more isolation.
Note also that if QCDMA for 3G would have been deployed in
Finland it would have disturbed the neighbouring
bands so much that one extra band would have been wasted.
That is because that 48 tap filter was "future" and
"optional", QCOM didn't use any FIR filtering, just
blasted the sky full of garbage..
Btw, even your old 56k modem has at least 128 tap filters,
only academic idiots with no real experience do 129 tap
filters (with MatLab, without any tool to properly optimize
them)
An ADSL modem has a lot more except if it too is cutting
corners.
Ilmarinen
That is, americans better stay out of spectrum and
guardband, out-of-band interference debates, but it is
a good way to keep FCC handicapped.
That "complex" filter is really fun, hilarious, probably
means the poor guy who got the propaganda job has half the
taps almost zero, the imaginary ones, ho-ho-ho...
Using half the wheels as propellers on a tractor
and then complaining the tractor still gets stuck in the mud, didn't make it into a helicopter.. |
